ubuntu install zsh
#The sudo apt-get update command is used to download package
#information from all configured sources
#So when you run update command, it downloads the package
#information from the Internet. It is useful to get info on
#an updated version of packages or their dependencies.
sudo apt-get update
sudo apt-get install zsh
#Now that ZSH shell is installed, you can check whether ZSH
#is working with the following command:
zsh --version